Turbine JMB VL3

Delta-hawk had an engine in a cirrus they flew to Oshkosh in 2014. Still nothing on the market. Yes, I'm jaded. Rotax 915IS is 185lbs. What little information I can find they say this engine weighs 176lbs.

Rotax 915 installed is 200 pounds on average.
 
This small turboprop has the best shot no question.
FYI: those micro-turbines have been around for a number of years to include those with recuperators. We just had a small PoA discussion on those engines in the Velocity V-twin thread last month which has 2 micro-turbines installed. The big play for those micro-turbines is on the e-flight side and not the LSA or conventional aircraft market and is the sole reason Safran bought into Turbotech.
 
The two turbines installed in the Velocity are PBS. 35GPH between the two engines. Twin Turbotech’s on a smaller platform could yield 240HP at 18GPH.
 
I like the idea of having a small turbine on the market. The only real benefit is/could be reliability and the fact it can run on just about anything with 100LL being constantly challenged. New designs in aviation only take off with hefty financial backing. I doubt the Rotax 912 would have ever been as popular as it is had it not been for the deep pockets of the company. You have to be able to take losses for several years until the volumes reach a profitable level. Very few startups can manage that on top of development cost.

The most recent company to really succeed in my opinion is Verner. They played the game well and are seeing the rewards. So they are proof it can happen, just luck of the draw.
 
Since when did E/AB require an approved engine?

They don't--never said they did. That particular post was in reference to the JMB VL3 airplane and/or kit, not the engine.
 
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They don't. That particular post was in reference to the JMB VL3 airplane and/or kit, not the engine.
It's funny, the jmb "dealer" in the us says it can be flown in any number of categories. SLSA is one of them. You can't claim cruise of 195 knots AND claim it can be flown as an SLSA. Now you're just lying and lost any credibility
 
It's funny, the jmb "dealer" in the us says it can be flown in any number of categories. SLSA is one of them. You can't claim cruise of 195 knots AND claim it can be flown as an SLSA. Now you're just lying and lost any credibility
Why not? Several companies play the game of having the same plane in both categories. All they do is change the rated power level. The real make it or break it number as to if it will fit into the slsa category is the stall speed.
 
Why not? Several companies play the game of having the same plane in both categories. All they do is change the rated power level. The real make it or break it number as to if it will fit into the slsa category is the stall speed.

You can already buy a VL3 as an SLSA, it’ll just have to be fixed gear and propeller. But you can still get respectable speeds with the 915 fixed pitch propeller combination as Bristell has already shown hitting 145 knots true at altitude and still staying within ASTM consensus standards.
 
The two turbines installed in the Velocity are PBS. 35GPH between the two engines. Twin Turbotech’s on a smaller platform could yield 240HP at 18GPH.
That would give an SFC that is on par with the absolute best of the PT6 engines, which is unlikely.
 
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It looks like my Bristell, not sure I'd strap a jet to such low-weight aircraft for practicality.

VL3 is quite a different animal being all composite but BRM just dropped photos of their turbine Bristell utilizing the same Turbotech engine.
 
I saw that today. It looks awesome with the longer nose. Still want to understand the specs

the VL3 would be awesome if it had a chance to be certified or if the FAA wouldn’t drag their ass like a dog w worms on mosiac.
 
Like others in this thread, I'm eagerly awaiting real-world experience of how the TurboTech engine truly performs in a light aircraft. I'm concerned about availability of parts and service for US customers, and of course if the specified performance numbers hold up. I'm not holding my breath!

In 5 years' time, I can see myself as in a position to justify owning a half share in a 2-seater experimental aircraft to operate in US and Canadian airspace. Perhaps a Jet-A burning E/AB like the VL3 is the ticket.
 
I'll start to get interested when a kit or certified aircraft is available with a turbine and it out performs what is currently offered. Keep us posted.
 
I saw a price tag of $50K floating around for the TP-R90 but I’d guess it’s more like $70K now. But with a 3000 hour TBO that’s almost 3X as long as the $41K 915 and at a close fuel burn.

This article says the TG-R90 will be 140,000 euros, close to $150k USD. (And that article is nearly a year old. Price has surely increased with the current rate of inflation.) I'd love a turbine, but not paying 3.5X the price of a Rotax 915iS for an engine with less power and similar fuel burn. TBO difference is insufficient to supplant the price difference, especially considering the 915iS TBO is targeted to be increased to 2000 in the not-too-distant future.

I still think it's promising, super-cool technology. Wishing these guys luck, and maybe they can bring the price down with scale in the future. In the meantime I think I'll keep my 915iS!
 
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Sorry if this is off topic, but according to the JMB website, they offer a fixed gear version. Any idea of the difference in cruise speed of the retractable? The website makes no mention of it, and there may not be any FG’s flying. If the difference is not that great, I would prefer the FG due to lower maintenance costs, not to mention insurance.

Ps, I’m not interested in the turboprop, just one of the 3 Rotax engines.
 
In theory the turbine engine is more reliable but there’s no data on this particular engine proving that.

Unless they are making it out of paper a Brayton cycle crushes an otto cycle.

Rotax has a sketchy history to begin with.

Also, who is saying you won't get an E/AB certificate with this engine? The FAA might give you more stage 1 hours, but ban it? Lol no.
 
Unless they are making it out of paper a Brayton cycle crushes an otto cycle.

Rotax has a sketchy history to begin with.

No more than any other internal combustion engines.
 
Unless they are making it out of paper a Brayton cycle crushes an otto cycle.

Rotax has a sketchy history to begin with.

Also, who is saying you won't get an E/AB certificate with this engine? The FAA might give you more stage 1 hours, but ban it? Lol no.

More to reliability than simply Brayton vs Otto. This is the first example of a heat exchanger turbine for this company in an aviation application. Until I see data showing several years of reliable service, I’m just not going to assume their word for it and that it beats out a Rotax.

Furthermore, what kind of scheduled maintenance is required? What type of support after the sale does the customer get? Parts availability / cost? What A&Ps are willing to work on it? Can easily find someone willing to work on a Rotax. Finding a mech that’s familiar with TurboTech could be a problem.
 
I'm pretty much convinced that the only way I'm ever going to get that turbine rush again is to play startup sounds of a PT6 in my headphones when starting the IO-540. Maybe I can wire it up to a heat exchanger to give a whiff of burning kerosene in the cockpit at just the right time.
 
As one of the naysayers, I feel like I should further explain where I stand. I would LOVE for this to become real. I'm rooting for them, I really am. Unfortunately I all too often see younger (i'm not old, I promise) people new to aviation buy into every new thing that gets announced. Until it's real, it's hard to imagine it'll ever materialize. That affects aviation, automotive, software (video games) and nearly every single industry unfortunately
It's much easier and natural to "believe" when you are young and haven't had much practical or life experience.

The older we get the more resistant to change typically are as well.

I'm all for youth, excitement, and innovation but I generally wait until any new tech has been proven out for at least a decade before jumping on the wagon even if it is something I'm really excited about.
 
It's much easier and natural to "believe" when you are young and haven't had much practical or life experience.

The older we get the more resistant to change typically are as well.

I'm all for youth, excitement, and innovation but I generally wait until any new tech has been proven out for at least a decade before jumping on the wagon even if it is something I'm really excited about.
Wouldn't say resistant to change. Just jaded from all the false hope.
 
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